1. Technical Field
Various embodiments of the inventive concept relate to a semiconductor apparatus having variable resistance characteristics, and a method for fabricating the same.
2. Related Art
With the rapid development of mobile and digital information communication and the consumer-electronics industry, studies on existing electronic charge-controlled devices have encountered limitations. Thus, new functional memory devices other than the existing electronic charge-controlled devices need to be developed. In particular, next-generation memory devices with large capacity, ultra-high speed, and ultra-low power consumption need to be developed to satisfy the demand of large capacity memories in main information apparatuses.
Variable resistive memory devices, which use resistive properties as a memory medium, have been suggested as the next-generation of memory devices. Typical examples of variable resistance memory devices are resistive random access memories (ReRAMs), phase-change RAMs (PCRAMs), magneto-resistive RAMs (MRAMs), and spin-transfer torque magnetoresistive RAMs (STTMRAMs).
Each of the variable resistive memory devices may include a switch and a resistor, and store data “0” or “1” according to the state of the resistor.
In particular, the PCRAM may include a phase-change to material which is stabilized to either a crystalline state or an amorphous state by heat and has a switching characteristic between the different resistive states. For example, the phase-change material may be a chalcogenide material, such as germanium-antimony-tellurium (Ge—Sb—Te, GST).
A resistance of the conventional resistive element, such as a variable resistance layer, increases over time. Thus, there is high demand for a method for avoiding the resistance of the variable resistance layer increase over time.